Tetrahalophthalates as flame retardant plasticizers for halogenated resins

ABSTRACT

A flame retarded composition containing tetrahalophthalate plasticizer and a halogenated resin is provided.

This application is a division, of application Ser. No. 068,987, filedAug. 3, 1979, which is now U.S. Pat. No. 4,298,517 which is acontinuation-in-part of Ser. No. 972,601 filed Dec. 22, 1978, nowabandoned.

BACKGROUND OF THE INVENTION

The present invention relates to a composition containingtetrahalophthalate plasticizer admixed with a halogenated resin. Thisinvention also comprehends the method of improving the flame retardancyof a halogenated resin by using tetrahalophthalate plasticizers.

Although polyoxyalkylene tetrahalophthalates are known in the prior artfor flame proofing materials, no teachings were found of using thismaterial as a plasticizer or a flame retardant for halogenated resinssuch as polyvinyl halides. U.S. Pat. No. 4,098,704 describes the use ofpolyoxyalkylene tetrahalophthalates as flame retardant finishes for 100%polyester fabrics. This is an entirely different application than fromthat of the instant invention which is related to the plasticization ofhalogenated resins. The compositions of this invention are prepared toobtain a proper balance between flame retardancy and plasticizationproperties and yet provide lower smoke values on combustion. U.S. Pat.Nos. 4,094,850 and 2,525,961 and British Pat. No. 1,505,450 describe theuse of haloalkyl esters of phthalates as flame retardant plasticizersfor resins including PVC. These compositions have the disadvantage ofcontaining labile aliphatic bromine groups which tend to give discoloredresins more easily upon heat processing. These compositions are alsomore expensive since they require the use of not readily availablebromoalcohols to form the diesters.

SUMMARY OF THE INVENTION

The present invention is directed to a composition comprisinghalogenated resin and a flame retardant plasticizer of the formula##STR1## wherein

(a) the ring can have all possible isomeric arrangements;

(b) R is selected from the group consisting of hydrogen, alkyl orsubstituted alkyl of 1 to 10 carbons, hydroxy alkyl of 2 to 10 carbons,and polyhydroxy alkyl of 3 to 10 carbons;

(c) R¹ is selected from the group consisting of hydrogen, an alkyl orsubstituted alkyl of 1 to 12 carbons and ##STR2##

(d) R² is selected from the group consisting of hydrogen and CH₃ --;

(e) p is an integer of 0 to 50;

(f) X is selected from oxygen or NH; and

(g) A is selected from Cl or Br.

This invention also comprehends the method of improving the flameretardancy of a halogenated resin by incorporating in the resin atetrahalophthalate plasticizer as described above.

The tetrahalophthalate of this invention is added to the halogenatedresin either alone or in combination with dioctyl phthalate (DOP) as aco-plasticizer. The tetrahalophthalate is added to the halogenatedresins in any convenient manner, such as by blending or milling to get auniform composition. For example, the ingredients are blended by hotmilling the mixture at 260°-350° F. for 1-4 minutes after fusion and themilled sheets are pressed at 360°-370° F. at 2000-3000 psi for 20 to 60seconds. Other ingredients such as stabilizers, fillers, flameretardants or smoke suppressants may also be present.

Representative compounds of this invention are: ##STR3##

The preferred compositions are: ##STR4##

The R in the above formulas is ##STR5## and A is Br or Cl.

A variety of halogenated resins are contemplated by this invention.Applicable poly(vinyl halide)s include homopolymers, copolymers, andpolymer mixtures, as for example:

1. Homopolymers--poly(vinyl chloride), poly(vinyl bromide), poly(vinylfluoride), poly(vinylidene chloride), poly(vinylidene fluoride) and thelike;

2. Copolymers--vinyl chloride-vinyl acetate, vinyl chloride-vinylalcohol, vinyl chloride-vinylidene chloride, vinyl chloride-vinylidenefluoride, vinyl chloride-diethyl maleate and the like; and

3. Mixtures--poly(vinyl chloride) and poly(dichlorostyrene), poly(vinylchloride) and vinyl acetate-vinyl chloride copolymer, poly(vinylchloride), poly(vinylidene chloride) and a copolymer of vinylchloride-diethyl maleate.

The term halogenated resin also includes halogenated polyolefins,halogenated polystyrene, halogenated polyesters and chlorosulfonatedpolyethylene (Hypalon).

The compound of this invention is a clear, almost colorless and odorlessliquid. It can be blended with all ingredients typically used withplasticized PVC (i.e., stabilizers, fillers, antimony oxide, and commonplasticizers) and can be used at levels from 1-100 parts per hundredparts resin.

The intent of the following Example is to illustrate the presentinvention and is not to be a limitation thereof. Flame retardancy of thenovel halogenated resin composition is evaluated by ASTM-D2863-74 togive oxygen index values. Smoke-density valves are determined by burning3×3×0.03 inch (6.8 grams) specimens in an NBS Smoke Chamber using theflaming mode in accordance with ASTM Special Technical Publication 422(1969) and NPPA 258-T "Smoke Generated by Solid Materials," May, 1974.The average of two values is reported.

EXAMPLE 1

To 1,392 g (3.0 moles) of tetrabromophthalic anhydride were added 1,050g (3.0 moles) of Methoxy Carbowax 350 in the presence of 22.0 g ofsodium acetate. The mixture was heated at 90° C. for 8 hours in anitrogen atmosphere. The reaction mixture was filtered hot to remove thesodium acetate. The analytical data were consistent with the assignedstructure: ##STR6##

EXAMPLE 2

To the compound of Example 1 were added 348.0 g (6.0 moles) of propyleneoxide and 2.0 liters of toluene. The mixture was heated at 60°-100° C.The solvent and residual propylene oxide were removed to give theproduct in almost quantitative yield. The analytical data wereconsistent with the assigned structure: ##STR7##

EXAMPLES 3-16

To a PVC resin were added various amounts of the compound of Example 2blended with dioctyl phthalate (DOP) in the following formulation:

    ______________________________________                                                          Parts                                                       ______________________________________                                        PVC resin           100.0                                                     Stabilizer (Argus Mark 2050)*                                                                     2.0                                                       Sb.sub.2 O.sub.3.   4.0                                                       Epoxidized Soybean Oil                                                                            3.0                                                       Plasticizer(s)      see TABLE A                                               ______________________________________                                         *Ba/Cd/Zn liquid stabilizer for flexible PVC                             

The ingredients were blended using a Waring Blender and then were hotmilled at 260°-280° F. for 2 minutes after fusion. The milled sheetswere then pressed at 360° F. at 2,000 psi for 30 seconds. TABLE A showsthe results:

                  TABLE A                                                         ______________________________________                                        Parts                                                                                               Phosphate                                                    Compound         Ester                                                   Ex.  of               (Kronitex 100**                                                                         Flammability                                                                           Smoke                                No.  Example 2 DOP    FMC)      LOI      Dmc                                  ______________________________________                                        3    --        60     --        27.5     519                                  4     6        54     --        27.5     514                                  5    12        48     --        28.2     529                                  6    18        42     --        28.8     471                                  7    30        30     --        30.7     489                                  8    42        18     --        32.7     469                                  9    60        --     --        38.1     429                                  10   --        60     --        27.5     528                                  11   --        54      6        27.5     565                                  12   --        48     12        27.5     540                                  13   --        42     18        27.5     663                                  14   --        30     30        28.6     683                                  15   --        18     42        30.7     545                                  16   --        --     60        32.1     610                                  ______________________________________                                         **Kronitex 100 = (CH.sub.3).sub.2 CH--C.sub.6 H.sub.4 --O(C.sub.6 H.sub.5     O).sub.2 P = 0(FMC).                                                     

These results indicate that 60 parts of the compound of Example 2 (seeExample 9) give less smoke on combustion when compared either to anequal amount dioctyl phthalate alone (see Example 3) or to an equalamount of a commercial plasticizer (Example 16).

EXAMPLE 17

Following the procedure and formulation of Examples 3-16, 30 parts of##STR8## and 30 parts of DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 18

Following the procedure and formulation of Examples 3-16, 30 parts of##STR9## and 30 parts of DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 19

Following the procedure and formulation of Examples 3-16, 30 parts of##STR10## and 30 parts DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 20

Following the procedure and formulation of Examples 3-16, 30 parts of##STR11## and 30 parts DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 21

Following the procedure and formulation of Examples 3-16, 30 parts of##STR12## and 30 parts DOP were added. This gave flame retardancy andsmoke value similar to that obtained by Example 7.

EXAMPLE 22

Following the procedure of Examples 3-16, 30 parts of the composition ofExample 2 were added to a formulation containing 100 parts of Hypalon(chlorinated polyethylene) resin. The final resin had enhanced flameretardancy properties.

EXAMPLE 23

Following the procedures and formulation of Examples 3-16, 30 parts of##STR13## and 30 parts of DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 24

Following the procedure and formulation of Examples 3-16, 30 parts of##STR14## and 30 parts DOP were added. This gave flame retardancy andsmoke values similar to that obtained by Example 7.

EXAMPLE 25

The procedure for Examples 3-16 was followed except the samples weremilled for 3 minutes at 300° F. to 340° F. and pressed for 1 minute at365° F. The following formulation was used:

    ______________________________________                                                                Parts                                                 ______________________________________                                        Geon EP 103F-76 PVC (Goodrich)                                                                          100                                                 Tribase XL Stabilizer (NL Industries)*                                                                  5.0                                                 Ross Wax 165 (Ross Co.)** 0.5                                                 Alumina Trihydrate (Alcoa)                                                                              30.0                                                Plasticizer (see below)   40.0                                                For the plasticizer component 28 parts of                                     dioctylphthalate and 12 parts of                                               ##STR15##                                                                    ______________________________________                                         *Tribase XL is a lead silicate sulfate PVC                                    **Wax to aid processing of PVC by acting as a lubricant.                 

were added. This gave an LOI (flammability) of 30.4 and a NBS smokevalue (Dmc) of 469.

EXAMPLE 26

Following the procedure and formulation of Example 25, 28 parts ofdioctylphthalate and 12 parts of ##STR16## were added. This gave an LOI(flammability) and NBS smoke value (Dmc) similar to that found inExample 25.

What is claimed:
 1. The process of smoke and flame retarding andplasticizing halogenated resins comprising adding to a halogenatedresin, 1 to 100 parts per hundred parts of resin of a plasticizer of thestructure: ##STR17## wherein (a) the ring can have all possible isomericarrangements;(b) R is selected from the group consisting of hydrogen, analkyl of 1 to 10 carbons, and polyhydroxyalkyl of 3 to 10 carbons; (c)R¹ is selected from the group consisting of a hydrogen, an alkyl or asubstituted alkyl of 1 to 12 carbons, or ##STR18## (d) R² isindependently selected from the class consisting of H and CH₃ --; (e) pis an integer of 4 to 50; (f) x is selected from O or NH; and (g) A isselected from Cl or Br so as to form a uniform composition.
 2. Theprocess of claim 1 wherein a mixture of the halogenated resin andplasticizer is hot milled at 260°-350° F. for 1-4 minutes after fusionto form a uniform composition and the milled sheets are pressed at360°-370° F. at 2000 to 3000 psi for 20 to 60 seconds.
 3. The process ofclaim 1 wherein the halogenated resin is PVC or its copolymer.
 4. Theprocess of claim 1 wherein one or more of plasticizers, fillers,antimony oxide, stabilizers and smoke suppressants are present.
 5. Theprocess of claim 1 wherein the halogenated resin is chlorosulfonatedpolyethylene.